Application of Biosynthetic Enzymes in HS and Heparin Oligosaccharide Synthesis

2 Application of Biosynthetic Enzymes in HS and Heparin Oligosaccharide Synthesis 

Chemoenzymatic synthesis of HS was first employed in the synthesis of structurally heterogeneous polysaccharides. In this method, a bacterial capsular polysaccharide isolated from the E. coli strain K5 is subjected to a series of enzymatic modifications, including N-sulfonation, epimerization, and 2-0-, 6-0-, and 3-O-sulfonations [26-28], 

SCHEME 9.1 Biosynthesis of HS. (a) Elongation reactions to prepare the precursor polysaccharide backbone using both EXT1 and EXT2 enzymes, (b) Polysaccharide modifications. 

Another impetus is to use the chemoenzymatic approach to synthesize structurally defined oligosaccharides. Early attempts targeted a single product from a specialized 

TABLE 9.1 Summary of HS/Heparin Oligosaccharides Prepared by the Chemoenzymatic Approach 

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